I am in the process of attempting to install an outside switch for a radon mitigation system. However, I am unable to drill through the remaining part of the block wall. I have an M12 Fuel hammer drill and a carbide drill bit. I imagine something is in the way but what? If it was concrete in the floor I would guess rebar. The first part went through like butter. I have pictures: https://imgur.com/a/hCed4u8
If it was concrete in the floor I would guess rebar
Rebar is used in hollow block wall too:
I’d remove one of those circular knockouts at the back of the wall box to drill an inch to the left or right.
Judging by how far it looks like your bit drilled through the wall it could also be that you were just having the absolute worst luck and managed to find a brick tie on your first attempt. If that’s the case then the good news is that you shouldn’t have a hard time avoiding them if you stay around the area you’ve already drilled into.